1. Technical Field
The present invention relates to a transfer device and an image forming device provided with the transfer device.
2. Related Art
In an electrophotographic image forming device, first, an image carrier such as a photosensitive body is electrically charged uniformly by a charging device, followed by exposure using an exposure device to form an electrostatic latent image. The electrostatic latent image thus formed is subjected to development using a developing device, whereby a toner image is formed on the image carrier. The toner image thus formed on the image carrier is transferred onto a recording sheet by a transfer device. The recording sheet with the toner image transferred thereon is subjected to fixing by a fixing device.
As the transfer device for transferring a toner image onto a recording sheet there is known, for example, corotron which transfers a toner image onto the recording sheet electrostatically without contacting the recording sheet and the image carrier. In such a non-contact type transfer device, the contact between the image carrier and the recording sheet becomes non-uniform and there may occur a lowering of transfer efficiency or a defective transfer.
To avoid the occurrence of such an inconvenience, there has been proposed a method wherein a transfer assisting blade is provided on an upstream side of the corotron to press the recording sheet against and into close contact with the image carrier (see, for example, Japanese Published Unexamined Patent Application No. 2000-242092).
However, as shown in FIG. 16A, if a recording sheet P wrinkles at X, it may be impossible to fully remove the wrinkles X because a front end 1022A of a conventional transfer assisting blade 1022 is in simultaneous and uniform abutment against the recording sheet P in the transverse direction of the sheet, as shown in FIG. 16B.
Consequently, in each wrinkled portion x shown in FIG. 16B, there arises a space (air gap) between the recording sheet P and the image carrier, and as the case may be there occurs a phenomenon that a part of a toner image is not transferred to the recording sheet P and a part of the image is dropped out. For this reason it is desired to further improve the adhesion between the image carrier and the recording sheet.
The above description is based on knowledge of the present inventors and not necessarily that known in the art.